There hasn't been a major US airline to go out bust since Pan Am about 15 years ago, other than TWA which was bought by and absorbed by American a few years ago. The chances of US Air actually going out of business in the next year or two are slim to none, in my opinion. United and US Air are operating in Chapter 11, Delta and several other airlines are dangerously close to Chapter 11, but it is another matter to actually put a major legacy airline out of business.
--Lan Sluder